An idea came to me a few days ago: since I love old palmtops and handhelds so much, and absolutely hate console cables, why not make use of the IR ports on those devices?

Wireless communication, no matter what kind, is just much cooler than doing it the wired way. So this is what I’ve been working on for the past few days.

The idea is simple: get a device that can talk both IR and modern Wi-Fi/Bluetooth. Naturally, I thought of the ESP32, and I just happened to have an M5Stack Cardputer lying around, which I bought several years ago.

The first challenge was finding a way to communicate with IrDA devices. Luckily, someone is already selling a TTL-to-SIR module. But judging from how the SIR transceiver works, and from the PCB layout, it should be easy enough to recreate with some time and patience.

The next challenge was integrating the SIR module into the Cardputer. Luckily, after a close inspection, I noticed that if I removed the magnets in the battery compartment, the free space was just enough to stuff the SIR module in. So in it went.

After cutting openings for the IR transceiver and the cable, the hardware side of things was basically done.

I’m not going to pretend otherwise here: Codex did about 90% of the coding work. But eventually, this is what I got: the Cardputer connects to modern Wi-Fi, then connects to a Telnet or SSH server, and finally relays all the data through the IR port.

In this way, any ancient device with a SIR/IrDA port can be used as a terminal — and can continue to be genuinely useful well into the foreseeable future.